Tag Archives: I2C

I2C or IIC (Inter-Integrated Circuit) is a simple bidirectional serial interface, which requires only 2 signal lines for data transfer. It was originally developed by Philips in 1980′s to provide easy on-board communications between a CPU and various peripheral chips in a TV set. Today, it is widely used in varieties of embedded systems to connect many low speed peripherals, such as external EEPROMs, sensors, LCD drivers, port expanders, real-time clocks, etc, to the host microcontroller. In this tutorial, we will explore the chipKIT Wire Library for establishing an I2C communication link between the chipKIT Uno32 board and two I2C sensors. The Uno32 board receives the sensor outputs through the I2C link and displays the results on the serial monitor window on the computer screen.

The Si7005 is a digital relative humidity and temperature sensor from Silicon Labs. It integrates fully factory-calibrated humidity and temperature sensor elements with an analog to digital converter, signal processing and an I2C host interface in a single monolithic CMOS sensor IC. The Si7005 is available in a “non hand-assembly-friendly” 4×4 mm QFN package, which requires reflow soldering to mount it on a PCB. This breadboard friendly breakout board is designed to make your prototype project with the Si7005 sensor much easier. It can be used with PIC, Arduino, or any other microcontroller development platform through an I2C bus. The power supply and I2C signal pins are accessible through breadboard friendly 0.1″ pitch header pins. Note that the Si7005 sensor is not 5.0V tolerant. It must be operated at 2.1-3.6V power supply.

Microchip Technology Inc. has announced a new six-member family of temperature sensor ICs called the EMC118X. This is the world’s first family of temp sensors with 1.8V SMBus and I2C™ communications, which is required for interfacing to the latest generation of smartphone, tablet and PC chipsets. Additionally, this integrated low-voltage I/O support reduces cost and board space because it is accomplished without an external voltage level shifter. These are also the first temp sensors to use an advanced sample-frequency-hopping filter, which enables temperature-monitoring traces of up to 8 inches in noisy environments with accurate readings. The EMC118X family serves a broad range of applications in the mobile, commercial and embedded computing markets, by combining the above features with options for dual, triple and quad temperature monitoring, along with hardwired system-shutdown settings that can’t be overridden by software.

A logic analyzer is an excellent tool for capturing many digital signals at once and displaying their timing relationships. It is particularly useful in verifying and debugging digital circuits. This tutorial is intended to provide a quick overview of a logic analyzer tool and its uses in analyzing and decoding data flowing on multiple signal lines or bus in a digital system. The logic analyzer tool is extremely helpful in troubleshooting problems arising from timing violations and transients on buses. In this article, I am going to use the SCANALOGIC-2 educational kit from IKALOGIC to illustrate very basic features of a logic analyzer.